Author(s): Graça, M.P.F. ; Valente, M.A. ; Silva, C.C. ; Peres, M. ; Cruz, A. ; Soares, M.J. ; Neves, A.J. ; Monteiro, T.
Date: 2009
Persistent ID: http://hdl.handle.net/10773/6085
Origin: RIA - Repositório Institucional da Universidade de Aveiro
Subject(s): Lithium niobate; Europium niobate; Glass–ceramics; Structural properties; Morphological properties; Optical properties
The sol–gel method was used to prepare a lithium niobiosilicate glass doped with europium ions, 91SiO2–4Li2O–4Nb2O5–1Eu2O3 (% mole). The dried gel was heat-treated between 500 °C and 750 °C and glass ceramics were obtained. X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman studies show that crystallization starts at temperatures above 600 °C. The LiNbO3 and EuNbO4 nanocrystals were found in the heat-treated samples as corroborated by the structural, morphological and optical properties. Room temperature photoluminescence (PL) studies allow us the identification of multiple Eu-related optical centres and the strongest red 5D0 → 7F2 intraionic transitions occur in the samples heat-treated at 600 °C where the LiNbO3 crystal phase was detected.
